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HydroICE Project Developing a Solar-Powered Combustion Engine
cylonlover writes "OK, first things first – stop picturing a car with solar panels connected to its engine. What Missouri-based inventors Matt Bellue and Ben Cooper are working on is something a little different than that. They want to take an internal combustion engine, and run it on water and solar-heated oil instead of gasoline. That engine could then be hooked up to a generator, to provide clean electricity. While that may sound a little iffy to some, Bellue and Cooper have already built a small-scale prototype."
Separating oil and water which have been mixed at such a fine level doesn't seem the easiest. While I know it can be done, can it be done in such a manner to maintain any of the heat energy which remains? Or does one just accept that energy as lost?
It is in fact a steam engine, using solar-heated oil to flash water to steam right in the cylinder.
And since TFA can't be arsed to state a single reason why one might choose this over, say, a Stirling heat engine, I'm going to assume there's no good ones.
While the engine may ideally just vaporize the water with hot oil, the reactions involved would eventually degrade the oil. Additionally, the separations processes are often 50% of the whole system's energy requirements, I just wouldn't see the viability of such a system. Now a heat exchanger for hot oil/water vaporization would wake a lot more sense, but it seems they want to generate a funding buzz with an internal engine spin.
It's not being burned, it's only being used as a heat carrier. Seems to me it would be more efficient to just heat the water directly, and use it in a steam turbine. What am I missing here?
... that Slashdot had been finally invaded by the 'run your ICE-powered device on water' fraudsters who are all over the car forums on the web now. Thankful to find its just a bad description of using steam expansion as part of a power stroke (BMW tested the same theory using steam generated or augmented by the engines cooling system a few years back, although it worked for them they couldnt get the costs of it to be viable)
For the record before anyone does start talking about vehicle water injection, it adds no power per se, all it does is increase implied octane ratings by adding better cooling and detonation control, exactly the same way a well-designed intercooler would but with the added risk that it steam-cleans the oil from the cylinder walls and probably shortens the engine life as a result. Not to mention the effect on the cat and tailpipe from the increased moisture in the exhaust
I have been a user for about 10 years. This ends Feb 2014. The site's been ruined. I'm off. Dice, FU
The last comment at the bottom of the article is a post by one of the project team, linking to a FAQ written in response to the comments.
http://hydroice.wordpress.com/
From the indiegogo campaign (yes, the summary neglects to mention this is a bloody crowdfunded uni project):
Efficiency: Both steam turbines and Stirling engines are known to be quite efficient, typically falling around the 40% efficiency range. We won’t know exactly where our HydroICE technology will fall until testing is complete, but we’ll be able to reach at least 15% efficiency with projections falling closer to 30%.
Manufacturing and cost: Both steam turbines and stirling engines are extremely precise machines and as a result, we see that reflected in the high price that it costs to manufacture and purchase one. This makes them economically feasible only for large industrial scale applications.
Yep, Stirling engines are too precise to be economically feasible, but similarly precise gasoline engines are so cheap that even with extra modifications they'll be feasible... right.
But I see it's already covered. Cute idea but like programming languages, there's thousands of cute engine designes that aren't practical for widespread use.
"Eve of Destruction", it's not just for old hippies anymore...
Instead of oil use liquid sodium! It would be way more efficient!
I just read TFA, and what is described is in no way a combustion engine. Nothing is combusted.
They seem to carefully avoid mentioning it, but most oils when preheated to 700 degrees F (holy cow) and atomized in air will burn pretty well. Probably the water addition is to prevent the cylinder walls from melting, or more likely prevent them from looking like a well seasoned cast iron pan (which would have serious issues WRT cylinder rings)
diesel's autoignition point (not flash point, you're already mechanically atomizing the vapor) is only like 400 degrees F.
diesel has a somewhat lower autoignition point than gasoline, but gasoline has a much lower flash point than diesel, weird but true.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
stirling engines are extremely precise machines
What, their fuel injectors? Old fashioned mechanical carburators?
Yeah I know the guy is trying to get at the wider temp fluctuations in cylinder and piston temp, unless you go uniflow which has whole nother kettle of fish, but its not really much of a problem.
See if you try to crank up the efficiency and power of a trad ICE, eventually you get all manner of predetonation (ping) and trouble keeping crankshaft loads low enough while not letting the valves float and it gets all technical very fast. With a stirling you just crank up the heat until you melt or deform the piston/cylinder. Its more easily understood so its easier to empathize so its "seems" harder, but actually ICE are way more difficult its just we can't talk in uneducated company about the actual challenges. Any moron can understand "it melted" so any moron thinks stirlings are more difficult because they can't even talk about ICE engine optimization.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Yes, they have reinvented the steam engine.
In this case, literally: it runs on stream. (As opposed to many more modern heat engines, which usually use other working fluids).
The innovation seems to be that they have separated the heat absorption from the expansion of the working fluid.
If the best they can do is 15%, it will not be competitive with photovoltaic, ever. This needs tracking and mirrors, and that kind of moving parts just can't beat the production efficiencies of silicon solar cells.
http://www.geoffreylandis.com
Most people think of "solar" or "wind" as renewable, but in fact, burning straw pellets could also work very well as a heat source and be carbon neutral (renewable). The nice thing about an engine like this is that any form of heat could drive it. Separating combustion from from the pressures in the engine also will eliminate NOx and other pollutants. So even if the solar part doesn't work out (or at night), this idea still has potential for carbon-neutral energy from just about any heat source that can heat up the oil.
I'd pay money to see the first run.
"Eve of Destruction", it's not just for old hippies anymore...
Yep, Stirling engines are too precise to be economically feasible,
I don't know about that. Stirling engines seem to be popular projects for people getting started with home machine shops. Their cost is a matter of production volume.
but similarly precise gasoline engines are so cheap
Right. Because they are high volume production items. But one must figure one's economics based upon the assumption that one will go into large scale production. Not scrounging a bunch of parts adapted from some other use. If this technology is to become viable, piston engines will be designed and built specifically for this purpose (or for Stirling engines) at a volume to keep production costs low. So in the final analysis, the engine costs will be based on the complexity and precision needed, which appear to be similar for piston engines.
Have gnu, will travel.
Or replace the water with potatoes and get French fries at the same time.
I just read TFA, and what is described is in no way a combustion engine. Nothing is combusted.
They seem to carefully avoid mentioning it, but most oils when preheated to 700 degrees F (holy cow) and atomized in air will burn pretty well.
Since they plan to recover and reuse all of the oil, they must be assuming a type of oil that won't burn at the temperatures used. The GP is right: according to the article there's no combustion in the process. The design is an unusual sort of steam engine.
Of course, this raises the question of why it's better than a more traditional solar-powered steam engine. It clearly avoids the need to deal with high-pressure steam anywhere except in the "combustion" chamber, and if it can work well in slightly modified ICE designs then we already have a lot of factories cranking out the base platform. I have to think that it's less efficient than a true multi-stage steam engine, though. We learned how to make those things really efficient many decades ago.
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...I see a few issues, some fixable, some less so.
First, while removing the boiler from the whole "steam plant" equation really does help the safety side of things, you have to be VERY VERY SURE that your separator removes ALL the water from your exhaust. Why? Because if you have even a tiny bit of water in your oil tank, and your heat it to 700F, it's going to boil and expand... and suddenly your low-pressure oil reservoir systems just turned into a really weak boiler full of oil that's hot enough to burst into flames. Instead of venting superheated invisible steam that can strip flesh from bones in seconds, you're going to be spurting oil around at temperatures that cause spontaneous combustion when meeting atmospheric oxygen. Not sure if that's really a step up.
Second, while oil and water don't mix, they do tend to form a really annoying to work with mayonnaise-like suspension of oil globules in water when mixed together really well. This takes a long time - or a lot of energy - to completely split apart.
Third, in addition to the previous problems with separating mayonnaise, heat dissipation will be an issue. Internal combustion engines carry a LOT of their waste heat away with exhaust, but in a closed-loop system like the one they're proposing here you need to remove the 85% of the energy you don't convert into work. Steamboats traditionally do this with a condenser that sits in the water, but if you're not near a large body of water, well... let's just say your condensing apparatus is going to be a huge, complicated, and difficult to work with because even if you don't have a high-pressure steam BOILER you're still going to have a high-pressure steam CONDENSER.
You could, of course, run the oil at a cooler temperature... but that drastically cuts back on your efficiency, because your power depends on having a lot of pressure inside the cylinder, and that pressure comes from the steam, and the pressure of the steam depends on the temperature... well, you get the idea. Basic thermodynamics.
So anyway. It's a cute idea, but unless they've got some really amazing tricks to solve the glaring technical fiddly parts I don't think it's going to get very far. I hope I'm wrong... but I don't think I am.
Never underestimate the stupidity inherent in all human beings.
In case anyone thinks this is interesting enough to throw money at it, I got this link from the FAQ page: http://www.indiegogo.com/hydroice.
I thought it was interesting enough to throw it a few bucks. Could be snake oil, but it could also be really cool.
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This is not a combustion engine, at all. It's an "insert water with hot oil, use generated steam to drive engine, separate back oil and water to reuse" engine.
The potential efficiency is interesting, and the reduction of generated hydrocarbons compared to a normal motor of the awkwardness of creating and handling lead-acid batteries or other awkward electrical energy storage is also interesting. The difficulty of doing reliable water and oil separation for long periods, at low cost and with low power cost, is an interesting one.
A quick review of the Wankel engine also shows that this technology might be better applied there. The engine destroying accidental misfires known to some Wankel designes would not occur, and the problems handling the spark plug or with lubrication also would not apply.
Interesting if it works.
- How hot is this engine going to get (safety)?
- Insulation? (as he says)
- Capture of waste heat? Something like this?
- How is solar energy transferred to oil? With parabolic trough?
- Energy loss due to vibration of one piston?
- Breakdown of oil?
- Any limit to length of pipe running through collector?
They seem to carefully avoid mentioning it, but most oils when preheated to 700 degrees F (holy cow) and atomized in air will burn pretty well. Probably the water addition is to prevent the cylinder walls from melting, or more likely prevent them from looking like a well seasoned cast iron pan (which would have serious issues WRT cylinder rings)
I don't think you read the article carefully enough.
1. hot oil + water = instant steam
2. steam pushes the piston down
3. the oil + steam get recycled
4. GO TO 1
The only input is solar energy to heat the oil.
The rest of the system works on a closed loop.
[Fuck Beta]
o0t!
It does not use the oil up.
The Solar Energy Generating Systems power plants in the Mojave Desert have been using parabolic mirrors to generate electricity via solar heat for nearly 30 years now, using oil as the heat transfer fluid.
"The sunlight bounces off the mirrors and is directed to a central tube filled with synthetic oil, which heats to over 400 ÂC (750 ÂF). The reflected light focused at the central tube is 71 to 80 times more intense than the ordinary sunlight. The synthetic oil transfers its heat to water, which boils and drives the Rankine cycle steam turbine, thereby generating electricity. Synthetic oil is used to carry the heat (instead of water) to keep the pressure within manageable parameters." From the Wikipedia article on the SEGS operation.
This format of a heat engine isn't "going" anywhere as it would work only on a stationary position where the sun loading could be high with steerable mirrors. You could use molten oil, water or any material you chose to act as a heat source for a heat expansion engine.
For mobile uses, it all comes down to kilocalories stored per kilogram. This solution "won't go anywhere" mobile.
Modern day robotics make precision a non-issue. And with Stirling engines you can use more ceramics in the hot section since it's not exposed to explosive forces or crazy high RPMs like a gas turbine. Plus we can use them for refrigerator compressors without any specialized refrigerant. What they don't presently have is rapid throttle response, much like a regular steam engine, and to get a lot of power, they need to be very large, which is not an issue for stationary applications.
“He’s not deformed, he’s just drunk!”
Interesting that the OP got instantly modded down. Suppose the article was about a new computer language and the article described it as a compiler when it really was an interpreter. Bullshit would be called immediately. Same level of error, different tech.
"Eve of Destruction", it's not just for old hippies anymore...
At this stage in development, efficiency isn't a big deal , unless it can be proven early on that it will always be too horrible compared to alternatives...and that only counts if there are alternatives.
What is interesting/important is it's potential as (pointed out lots of times in the comments) a steam engine that avoids big boilers and has the same kick as an ICE since it uses the same mechanical layout. Any other heat-driven engines that can do the same? same kick, same overhead?
reading comments seems to say no so far: Stirling engines don't have the variable torque output for use in cars. Steam boilers are too heavy and involve piping steam around the system (dangerous and complex). Even converting the sunlight directly to electricity runs into storage problems (batteries aren't big enough yet) . I've seen come comments that heated oil may actually be a good way to store solar energy...not sure if it beats batteries, but worth a look.
This is another tool in the toolbox if it works. Is there anything that says this won't?
AB HOC POSSUM VIDERE DOMUM TUUM
I should think the water won't last long in the oil as its being heated to 700 degrees, the watter should boill off and be recoverable with a condensor. This is assuming that you would want a closed circuit for the water.
If the plant isn't efficient as per "energy out" / "energy in" it could still be efficient as per "total energy out lifetime" / "total cost in dollars lifetime".
"better ways of doing things eventually just replace the inferior things" - Linus Torvalds 09-08-07
"But one must figure one's economics based upon the assumption that one will go into large scale production."
That creates a chicken and egg scenerio. Unless you have some massive VC capital backing you then you need to be able to produce units at reasonable prices in small volumes at first. Or else your technology will be overpriced, nobody will buy it, and you will never survive large enough to reach 'large scale production'.
There are dozens of companies that make this mistake every day. If you don't have a bankroll that can produce mass quantities from the get go and float you until you sell them, you need to sell to someone who can, or be able to turn a profit at low volume production.
Water injection dates back to the 1920s. It was used because the technology of the day could not use high compression ratios without detonation. Modern technology overcomes detonation by attention to fuel, gas flow, thermal design and ignition timing. Water injection is obsolete.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
According to TFA 15% is the same efficiency as photovoltaic but the cost of the system is supposed to be 1/3 of equiv photovoltaic.
Yes, they said that, but they're wrong. No possible way it can get down to 1/3 the cost of photovoltaic panels. I frankly doubt if they can make it as low as twice times the cost of photovoltaic.
On a large enough scale, I think a Brayton engine might make it cheaper than photovoltaic, but part of that is because of the high efficiencies, and the other part the economy of scale of large turbines. I doubt a piston engine can be that cheap, not operating at these temperatures.
Maybe they're thinking about the photovoltaic cost of twenty years ago. PV has gone WAY down in the last few decades.
http://www.geoffreylandis.com
What they don't presently have is rapid throttle response, much like a regular steam engine
Which, frankly, would hardly matter in a hybrid car with electric traction and battery + supercap storage, would it?
Ezekiel 23:20
You really have to take into account potential reduction in costs for any technology meant to compete with photovoltaics (not saying this doesn't have that potential).
I don't understand... can you make a car analogy?
can't sleep slashdot will eat me
Precisely. Stirling engines have their niche: they make almost no sound, and work well under slowly varying loads. They are used for power generation in many applications. They have also been used in submarines for extremely quiet operation, both by marine explorers like Cousteau and by some navies. There have even been efforts to use them in small airplanes, since their output increases with altitude, while ordinary engines have less output at high altitude. I don't think they've made them successful in airplanes, however.
for i in `facebook friends "=bday" 2>/dev/null | cut -d " " -f 3-`; do facebook wallpost $i "Happy birthday!"; done
much like a regular steam engine, and to get a lot of power, they need to be very large, which is not an issue for stationary applications.
stirling engines are extremely precise machines
What, their fuel injectors? Old fashioned mechanical carburators?
A Stirling engine is *not* what you find inside any typical car. A Stirling engine is an external combustion engine (the heat source is provided from outside the engine) rather than the internal combustion engines (Otto cycle for gasoline cars and Diesel cycle for diesel vehicles) typically used. A Stirling engine has neither fuel injectors nor carburators - as an external combustion engine, it doesn't need to get fuel into the cylinders.
Don't get me wrong; it's a good idea, but I don't see its application beyond power plants.
It's mainly high compression ignition that results in NOx. That's why separating the combustion from the piston would really help, if we could do the energy conversion efficiently.
I should think the water won't last long in the oil as its being heated to 700 degrees, the watter should boill off and be recoverable with a condensor.
Only if the water is still steam when it exits the expansion chamber -- which should be easy enough to achieve by balancing the amount of oil and water injected, taking the temperatures of both into consideration.
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Maybe they'll use a centrifuge. Maybe electrostatic separation.
Maybe they'll heat the oil with a peltier and use the cool side as "a serious refrigeration unit".
All of those take energy that would sap the efficiency of the system. I'd probably go with a large condensation box that has baffles in it like a septic tank to keep disturbances down. As the liquids cool and travel through/around the baffles, they're slowed and turbulence is minimized.
You might not need a 100% efficient separation system to make it work.
Still, I don't see it being more efficient at this point than traditional steam engines and turbines.
I don't read AC A human right
The cost for X amount of steel, y amount of machining, z for mirrors, etc...
The costs for PV panels has dropped substantially. At this point I think that only large scale thermal solar will beat it's economy.
I don't read AC A human right
I wonder how much energy can be stored in heated oil compared to batteries. Quick back of the envelop calc shows, 20 gallons of oil, that is about 60 Kg. Specific heat of water is 1 cal/gm/degree, is 60,000 cal/deg, 470 deg over ambient, gives, 60,000x470=2.8e07 cal, or 1.2e08 Joules, or 2.85 Kg of gasoline at 42 MJ/Kg. That is about 0.95 gal of gasoline. 60 Kg battery pack can probably store more energy than 1 gal of gas. And that energy converts to mechanical power at a much greater efficiency than any heat engine. It does not look like an application for cars. May be cheaper fixed installations competing with solar panels may be. May be if the build a tiny steam turbine, it would be more efficient.
Small gas turbines are quite familiar to engineers, all the turbo-charged ICEs use a gas turbine in the exhaust manifold to pack more air into the inlet manifold. So small gas turbines are well understood, but still they are not usually found in the power ranges needed to drive cars and trucks. Heck, even railway locomotives go for 16 cylinder diesels than gas turbines. I wonder why.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
A fax machine that can send and receive e-mail? That would be marketable for legal offices...
I know tobacco is bad for you, so I smoke weed with crack.